Gas-burning kiln



`J. W. SNOW GAS BURNING .KILN

Filed Jan. 2l )Q22 May 13, 1924.

Patented May 13, 1924.

UNITED STATES "PATENT OFFICE.

JOHN W. sNoW, or rnnnron, NEW ann-snif.

GAS-BURNING KILN.

Application med January 2r, 1922. sel-iai No. 530,870. f

Kilns, of 'which the following is a specifica.

tion.

The object of this invention is to provide im rovements in kilns, designed particularV y for the firing of porcelain and similar articles, and'y particularly that type of kiln in which the heat firing is created by the combustion of illuminating or a similar gas.

Primarily, gas-burning kilns have inherent advantages over those Which depend for their heat upon a coal or coke tire, in that the former eliminates all of the dirt incident to the operation of the latter', besides being less expensive in'upkeep, as not only the same but greater temperatures may be obtained 4with the use of gas than are possible 'Witl'i the 'use of'coal or coke in shorter time.

Furthermore, the usual `blower or other draft-forcing' means necessarily incident to the operationr of a coal or coke kiln are eliminated` in one which rconsumes gas as its fuel, and one or more kilns of the latter type can be operated eiiicientfly yby one `man unassistedyivhile it is both advisable and necessary in the former type to employr at least two men for the operation oit' each kiln, in addition to the fact that the heat from the gas can be more evenly distributed `and better regulated throughout the entire length o the same than ispossible With a coal or coke heated kiln, With the result that in the former there isv possible", 98% output of the Ware originally loaded into the kiln orliring, While in the latter type approximately only 85% output can be 'depended upon.

It has been oundin practice that the iinf proved gas-heated'kiln hereinafter described in ldetail can be raised to ay temperature of 1750o F. Within? hours, and alter shutting ofi the fuel supply it Will cool in 5 hours, While a coal or coke `heated kiln of the same capacity requires from v9 to 12 hours to attain the same temperature, and cannot be cooled in less than 12 toI 18 hours after dumping the grates. f f

This invention therefore has for its object more specifically to provide a construction Which will permit a kiln to be eiiiciently heated by means of gas and accomplish the detailed functions and advantages hereinbetore referred to, all of Which is fully brought out ,in the following description, when read in conjunction With the accompanying draw* ings, in which Fig. 1 is a side elevation'of the preferred embodiment of the invention; and Fig. 2 is a transverse view of the same, one-half of Which is shown in vertical section, While the other half is sho-Wn in front elevation.

Referring to the drawings, the improved kiln comprises oppositely positioned side Walls 1 of brick or similar material,'sup ported upon spaced piers 2, providing between them alternately positioned air inlets 3,' While the upper portions ofsaid Walls are i enlarged at l to extend towards each other, but remain quite Widely separated inorder tolprovide an outlet 5 extending substantially the entire length ofthe kiln, said o-utlet being lined upon opposite sides by any suitable refractory material such as irebrick 6, and closed at the top by means of `a cover 7 which is supported directly by the linings as the latter extend vertically above the uppermost portions oi' the said Walls 1.

Preferably embedded Within the brickv construction of the side Walls are' longitudinally extending angle-irons 8, which are spanned upon each side by verticallyextending channel-ironsv or I-bearns 9, secured to'- gether both at their uppery and loWermost portions by means of tie-rods 10.A Said side vWalls are furthermore connected` at their front and rear by vertically extending Walls 11. Which are Aprevented from Warpingor lnilgineT by means of vertically eiitending channel-irons 12, inturn connected at their upper and loWer portions by means of tierodsl 13. H

The fronty Wall of the kiln is provided With any suitably shaped opening 14, adapted to be normally closed by independently operable doors 15, Which latter may be hinged as shoWn at 16 or otherwise `mounted so as to move into and away from the normally closed positions as shown in the right half of Fig 2. The contour'ofthe opening l'corresponds `and compares directly vWith 'the shell of tile comprising side Walls 17, Connected at the top by an arched lsection 1S,`and entirely open at the bottom 19.` Said shell is supported in any suitable manner above the grate 20, supported upon and level with the uppermost portions of the several piers 2, said grate being prol vided with centrally positioned enlargedv apertures 22, through which extend pipes 23, which together comprise the inner end portions of the system of burners provided for the purpose of heating the interior of the kiln, said grate 2() and bricks 21 in effect forming a substantially horizontally extending partition within said side walls beneath the chamber surrounded by the said shell.

The pipes 23 are connected at their lower ends by means of Ls 24 with a pipe 25 which extends horizontally outwardly through the several spaces 3 between the piers 2, said last-named pipes being provided upon their outer ends with any well-known type of means 26 for regulating the mixture of air with the fuel gas flowing into said means by way of the regulating valve 27 from a common supply pipe 28.

The inner surfaces of the side wallsl of the kiln are lined with {ire-brick 29 extending from the level of the grate 2O upwardly and merge into curved sections of fire-brick 30, which line ythe correspondingly shaped inner surface portions of the enlargements 4 of said side walls, said last-named sections communicating directly with the lower portions of the neighboring flue-linings 6. A series of transversely extending peep-holes 31 is provided in each of the said side walls, each of said holes being in alignment with the upper end portion of the respective pipe 23 in alignment with which it is directed, while said peep-hole is preferably formed by means of a suitable pipe or nipple 32, and normally closed at its outer end by means of a pivotally mounted slide or door 33. These holes are for the purpose of examining the condition of the respective flames within the kiln, and are known as checkerholes, while those just described are for the individual burners, the front wall 11 being provided with a similar checker-hole 34 normallyj closed by a door 35, and positioned in longitudinal alignment lwith each of the series of vertically extending pipes 23.

In the operation of this improved kiln, the fuel gas is lighted at the upper end of each of the pipes 23 and the intensity of the llame regulated by each of the respective valves 27. -As before stated, air and gas are mixed in proper proportions within the mixing means or Bunsen burner 26, but which air supply is great-ly augmented by the free flow of air through the spaces between the `piers 2 and into that portion of the kiln situated beneath the grate 20, whence the inowing air passes around the pipes 23 and through the respective apertures 22 in the bricks 21, and the air unites with the burning ames of gas to raise the temperature above that which would otherwise be possible in the kiln, and also insures a greater draft and larger quantity of heat-conducting air currents for the purpose of passing upwardly through the Hue 36 between the chamber surrounded by the tile walls 17-18 and the linings 29 of the side walls spaced therefrom.

It has been found in practice that the intense heat generated beneath the firing chamber, together with the free inflow of air through the spaces 3 and apertures 22 has a tendency to permit an extremely large amount of heat passing as before stated through the flues 36, and thence through the exit 5 and stack 37 leading therefrom. This loss of otherwise extremely valuable heat may be effectively diminished, and the escape of the heated air currents as referred to may be effectively checked by providing transversely inwardly extending ports or checker-holes 38 through the upper portions of the side walls 1, preferably at the base of the curved arched portion 30, said holes preferably being lined by means of tubes 39, the outer ends of which can be opened and closed to any desired degree by means of pivotally or slidably mounted doors 40.

Thus it will be seen that while the ports 32 and 33 resemble each other in the drawings, they perform an entirely different function depending upon their locations, the first as previously stated being for the purpose of observing thecondition of the flames playing about the respective burners, while the latter are for the express purpose of effecting the draft conditions within the flues 36, and thereby indirectly the heat condition within the firing-chamber. In fact upon burning a certain quantity of fuel gas, as hereinbefore described, with the doors 40 in closed position, a certain temperature can be obtained within the firing chamber, but this temperature it has been 'found will be increased many'degrees with the same consumption of gas fuel upon opening said doors 40.

Having thus described my invention, what I claim and desire to protect by Letters Patent of the United States is 1. A kiln, comprising the combination of side walls, a tile-inclosed chamber within and spaced from said side walls to provide fines between said chamber and side walls, said chamber being open at the bottom, a horizontally extending partition beneath said `chamber and provided with an enlarged aperture, fuel-gas-and-air mixing means extending freely through said aperture to direct a flame towards said chamber, and an aperture provided in one of the side walls to admit additional air to pass through said partition apertures and vunite with the gas and air mixture above said partition in the region of the flame.

2. A kiln, comprising the combination of side walls, a chamber closed about its sides and top and positioned-within and spaced away from the inner surfaces of said walls to provide a iiue therebetween having anv exit, gas-and-air mixing means to provide a flame beneath said chamber, and vents extending through the upper portions of said side walls and provided With adjustable closures, to admit varying amounts of cool air into said flue to maintain the heat of combustion within and around said chamber, and prevent the otherwise rapid escape of said heat through said exit.

3. A kiln, comprising the combination of side Walls, a chamber closed about its sides and top and positioned Within and spaced away from the inner surfaces of said walls to provide a flue therebetween having an exit, a horizontally extending partition beneath said chamber and provided with an enlarged aperture, means to direct a mixture of fuel-gas-and-air mixture through said aperture to provide a iame beneath said chamber, an aperture in one of the said side Walls to admit further quantities of air beneath said partition and through said partition aperture to unite with the gases of combustion in the region of said flame, and a port in the upper portion of said side wall 'which when opened reta-rds the escape of stead maintains the said heat within and around said chamber.

In testimony whereof I have ailxed my signature.

- JOHN W. SNOW. 

